Thin film semiconductor material produced through reactive sputtering of zinc target using nitrogen gases

ABSTRACT

The present invention generally comprises a semiconductor film and the reactive sputtering process used to deposit the semiconductor film. The sputtering target may comprise pure zinc (i.e., 99.995 atomic percent or greater), which may be doped with aluminum (about 1 atomic percent to about 20 atomic percent) or other doping metals. The zinc target may be reactively sputtered by introducing nitrogen and oxygen to the chamber. The amount of nitrogen may be significantly greater than the amount of oxygen and argon gas. The amount of oxygen may be based upon a turning point of the film structure, the film transmittance, a DC voltage change, or the film conductivity based upon measurements obtained from deposition without the nitrogen containing gas. The reactive sputtering may occur at temperatures from about room temperature up to several hundred degrees Celsius. After deposition, the semiconductor film may be annealed to further improve the film mobility.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 13/765,198 (APPM/11924.C1), filed Feb. 12, 2013, whichapplication is a continuation of U.S. patent application Ser. No.13/074,783 (APPM/11924.D1), filed Mar. 29, 2011 and issued as U.S. Pat.No. 8,398,826, which application is a divisional of U.S. patentapplication Ser. No. 11/829,037 (APPM/11924), filed Jul. 26, 2007 andissued as U.S. Pat. No. 7,927,713, which claims benefit of U.S.Provisional Patent Application Ser. No. 60/914,582 (APPM/11924L), filedApr. 27, 2007, each of which is herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention generally relate to a high mobilitythin film semiconductor material produced through reactive sputtering ofa zinc sputtering target using nitrogen containing gases under both lowand high temperature conditions.

2. Description of the Related Art

The electron mobility of a semiconductor layer has a very strong effecton the speed of the device and the current which may be driven throughthe device. The higher the electron mobility, the faster the speed ofthe device and the higher the source-drain current under the samevoltage. In recent years, amorphous silicon and polysilicon have beenthe semiconductor layers of choice for field effect thin filmtransistors (TFTs), for backplane to drive liquid crystal displays(LCDs), organic light emitting diode (OLED) displays, and quantum dotdisplays, and to build solar cell panels. Amorphous silicon may have anelectron mobility as high as about 1 cm²/V-s. Low temperaturepolysilicon may have an electron mobility higher than 50 cm²/V-s, butrequires a complicated process step such as laser annealing to achievethe electron mobility. Therefore, the cost of producing polysilicon withan electron mobility higher than 50 cm²/V-s is very high and notsuitable for large area substrate applications.

In a field effect transistor (FET), the semiconductor material createsthe channel between the source and drain electrodes. Without a voltagesupply to the gate electrode, no current may go through the source-drainelectrode even with a voltage between the source-drain electrodes. Asvoltage is supplied to the gate electrode, mobile electrons inside thesemiconductor layer will accumulate in the area very close to theinterface between the gate dielectric layer and the semiconductor layer.The semiconductor layer becomes conductive, and electrodes may gothrough the source-drain electrode easily with a low voltage between thesource-drain electrodes. High mobility of the semiconductor materialsindicates the mobile electrons in the semiconductor are more sensitiveto the electric field created by the gate electrode, and thesemiconductor channel becomes more conductive. The semiconductormaterial determines the current which may go through the semiconductorchannel influenced by voltage applied across the gate and sourceterminals. The greater the mobility of the semiconductor material, theless voltage is needed to achieve the current required across the FET.

Amorphous silicon may rely upon hydrogen passivation to achieve adesired mobility in a TFT. The amorphous silicon may be deposited bychemical vapor deposition (CVD) at temperatures up to about 350 degreesCelsius. The hydrogen passivation, while helping the amorphous siliconachieve the desired mobility, may not be stable such as TFT's thresholdvoltage to change with time under gate electrode voltage and underrelatively high temperatures created by the device itself.

Therefore, there is a need in the art for a stable semiconductormaterial having sufficiently high mobility not only on glass substrateswith high process temperatures, but also on plastic substrates and otherflexible substrates.

SUMMARY OF THE INVENTION

The present invention generally comprises a semiconductor film and areactive sputtering process used to deposit the semiconductor film. Thesputtering target may comprise zinc, which may be doped with aluminum orother metals. The zinc target may be reactively sputtered by introducinga nitrogen containing gas and an oxygen containing gas to the chamber.The amount of nitrogen containing gas may be determined by a filmstructure which does not have the typical zinc oxide signature peakssuch as a zinc oxide (002) peak as measured by XRD. The nitrogencontaining gas flow may be selected so that the film is amorphous (i.e.,no clear peaks as measured by XRD) or with some weak peak of zincnitride or zinc oxynitride. The nitrogen containing gas flow may besignificantly greater than the oxygen containing gas flow. The amount ofoxygen containing gas may be based upon a turning point of the filmstructure. The amount of oxygen containing gas may be selected to beless than the amount necessary to produce a zinc oxide (002) peak asmeasured by XRD. In order to simplify the process, the oxygen containinggas flow may also be determined through the film transmittance, a DCvoltage change, or the film conductivity based upon measurementsobtained from deposition without the nitrogen containing gas since theyare related to the film structure. The film created may be adjusted toamorphous or crystalline structure in certain levels. The reactivesputtering may occur at temperatures from about room temperature up toseveral hundred degrees Celsius. After deposition, the semiconductorfilm may be annealed to further improve the film mobility.

The film may have no clear zinc oxide peaks as measured by XRD, althoughan oxygen content of the film may be 25 percent of more. In oneembodiment, the film may have no peaks of Zn₃N₂. In another embodiment,one or more peaks of Zn₃N₂ may be present as measured by XRD. The filmmay comprise zinc, oxygen, nitrogen, and other metallic species dopedinto the film such as aluminum. The film may have nitride or nitritebonding as measured by XPS. The film may have an optical absorption edgebetween about 400 nm to about 1,000 nm and a band gap of about 3.1 eV toabout 1.2 eV. Since the semiconductor film is produced based upon thefilm structure, the semiconductor film may be produced under differentprocess temperatures, different powers, and even using different productplatforms.

In one embodiment, a sputtering method is disclosed. The methodcomprises disposing a zinc target in a sputtering chamber, flowing asputtering gas into the chamber, the sputtering gas comprising an oxygencontaining gas and a nitrogen containing gas, applying a bias to thetarget, and depositing a semiconductor layer on a substrate, thesemiconductor layer comprising the zinc, oxygen, and nitrogen.

In another embodiment, a sputtering method is disclosed. The methodcomprises flowing a nitrogen containing gas and an oxygen containing gasinto a sputtering chamber, the chamber having a metal target comprisingzinc and sputter depositing a semiconductor layer onto the substrate,the semiconductor layer comprising zinc, oxygen, and nitrogen.

In another embodiment, a semiconductor film, comprising zinc, oxygen,and nitrogen is disclosed. In another embodiment, a semiconductor filmcomprising zinc and having a mobility of greater than about 5 cm²/V-s isdisclosed. In another embodiment, a semiconductor film, when measuredusing x-ray diffraction, having a first peak of Zn₃N₂ at 2 theta andabout 31.5 degree having a possible (222) orientation and a second peakof Zn₃N₂ at 2 theta and about 39 degrees having a possible (411)orientation is disclosed. Other Zn₃N₂ peaks such as at 2 theta and about36.7 degrees having a possible (400) orientation could also be observedas shown in FIG. 3F.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a schematic cross sectional view of a sputtering chamber thatmay be used to deposit the semiconductor film according to oneembodiment of the invention.

FIGS. 2A-2E are XRD graphs for films showing the formation of zinc andzinc oxide peaks as a function of oxygen gas flow.

FIGS. 3A-3F are XRD graphs for showing the formation of a semiconductorfilm according at various nitrogen gas flow rates according to oneembodiment of the invention.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiments withoutspecific recitation.

DETAILED DESCRIPTION

The present invention generally comprises a semiconductor film and thereactive sputtering process used to deposit the semiconductor film. Thesputtering target may comprise zinc. In one embodiment, the target maycomprise zinc with a purity of 99.990 atomic percent or greater,preferably 99.995 atomic percent or greater. In another embodiment, thetarget comprises zinc doped with one or more doping metals. For example,the target may comprise zinc doped with between about 1 atomic percentto about 20 atomic percent aluminum. The zinc target may be reactivelysputtered by introducing a nitrogen containing gas, an oxygen containinggas, and argon to the chamber. The amount of nitrogen containing gas maybe significantly greater than the amount of oxygen containing gas andthe amount of argon gas. The amount of oxygen containing gas may bebased upon a turning point of the film structure, the filmtransmittance, a DC voltage change, or the film conductivity based uponmeasurements obtained from deposition without the nitrogen containinggas. The reactive sputtering may occur at substrate temperatures fromabout room temperature up to several hundred degrees Celsius. Afterdeposition, the semiconductor film may be annealed to further improvethe film mobility. It is to be understood that while description belowmay describe the target bias as DC, AC bias may be used as well.

The reactive sputtering method is illustratively described and may bepracticed in a PVD chamber for processing large area substrates, such asa 4300 PVD chamber, available from AKT, a subsidiary of AppliedMaterials, Inc., Santa Clara, Calif. However, because the semiconductorfilm produced according to the method may be determined by the filmstructure and composition, it should be understood that the reactivesputtering method may have utility in other system configurations,including those systems configured to process large area roundsubstrates and those systems produced by other manufacturers, includingroll-to-roll process platforms. It is to be understood that while theinvention is illustratively described below as deposited by PVD, othermethods including chemical vapor deposition (CVD), atomic layerdeposition (ALD), or spin-on processes may be utilized to deposit theinventive films.

FIG. 1 is a cross-sectional schematic view of a PVD chamber 100according to one embodiment of the invention. The chamber 100 may beevacuated by a vacuum pump 114. Within the chamber 100, a substrate 102may be disposed opposite a target 104. The substrate may be disposed ona susceptor 106 within the chamber 100. The susceptor 106 may beelevated and lowered as shown by arrows “A” by an actuator 112. Thesusceptor 106 may be elevated to raise the substrate 102 to a processingposition and lowered so that the substrate 102 may be removed from thechamber 100. Lift pins 108 elevate the substrate 102 above the susceptor106 when the susceptor 106 is in the lowered position. Grounding straps110 may ground the susceptor 106 during processing. The susceptor 106may be raised during processing to aid in uniform deposition.

The target 104 may comprise one or more targets 104. In one embodiment,the target 104 may comprise a large area sputtering target 104. Inanother embodiment, the target 104 may comprise a plurality of tiles. Inyet another embodiment, the target 104 may comprise a plurality oftarget strips. In still another embodiment, the target 104 may compriseone or more cylindrical, rotary targets. The target 104 may be bonded toa backing plate 116 by a bonding layer (not shown). One or moremagnetrons 118 may be disposed behind the backing plate 116. Themagnetrons 118 may scan across the backing plate 116 in a linearmovement or in a two dimensional path. The walls of the chamber may beshielded from deposition by a dark space shield 120 and a chamber shield122.

To help provide uniform sputtering deposition across a substrate 102, ananode 124 may be placed between the target 104 and the substrate 102. Inone embodiment, the anode 124 may be bead blasted stainless steel coatedwith arc sprayed aluminum. In one embodiment, one end of the anode 124may be mounted to the chamber wall by a bracket 130. The anode 124provides a charge in opposition to the target 104 so that charged ionswill be attracted thereto rather than to the chamber walls which aretypically at ground potential. By providing the anode 124 between thetarget 104 and the substrate 102, the plasma may be more uniform, whichmay aid in the deposition. To reduce flaking, a cooling fluid may beprovided through the one or more anodes 124. By reducing the amount ofexpansion and contraction of the anodes 124, flaking of material fromthe anodes 124 may be reduced. For smaller substrates and hence, smallerprocessing chambers, the anodes 124 spanning the processing space maynot be necessary as the chamber walls may be sufficient to provide apath to ground and a uniform plasma distribution.

For reactive sputtering, it may be beneficial to provide a reactive gasinto the chamber 100. One or more gas introduction tubes 126 may alsospan the distance across the chamber 100 between the target 104 and thesubstrate 102. For smaller substrates and hence, smaller chambers, thegas introduction tubes 126 spanning the processing space may not benecessary as an even gas distribution may be possible throughconventional gas introduction means. The gas introduction tubes 126 mayintroduce sputtering gases from a gas panel 132. The gas introductiontubes 126 may be coupled with the anodes 124 by one or more couplings128. The coupling 128 may be made of thermally conductive material topermit the gas introduction tubes 126 to be conductively cooled.Additionally, the coupling 128 may be electrically conductive as well sothat the gas introduction tubes 126 are grounded and function as anodes.

The reactive sputtering process may comprise disposing a zinc sputteringtarget opposite a substrate in a sputtering chamber. The zinc sputteringtarget may substantially comprise zinc or zinc and a doping element.Suitable dopants that may be used include Al, Sn, Ga, Ca, Si, Ti, Cu,Ge, In, Ni, Mn, Cr, V, Mg, Si_(x)N_(y), Al_(x)O_(y), and SiC. In oneembodiment, the dopant comprises aluminum. The substrate, on the otherhand, may comprise plastic, paper, polymer, glass, stainless steel, andcombinations thereof. When the substrate is plastic, the reactivesputtering may occur at temperatures below about 180 degrees Celsius.

During the sputtering process, argon, a nitrogen containing gas, and anoxygen containing gas may be provided to the chamber for reactivesputtering the zinc target. Additional additives such as B₂H₆, CO₂, CO,CH₄, and combinations thereof may also be provided to the chamber duringthe sputtering. In one embodiment, the nitrogen containing gas comprisesN₂. In another embodiment, the nitrogen containing gas comprises N₂O,NH₃, or combinations thereof. In one embodiment, the oxygen containinggas comprises O₂. In another embodiment, the oxygen containing gascomprises N₂O. The nitrogen of the nitrogen containing gas and theoxygen of the oxygen containing gas react with the zinc from thesputtering target to form a semiconductor material comprising zinc,oxygen, and nitrogen on the substrate.

In order to determine the desired oxygen flow rate for forming thesemiconductor film, the amount of oxygen may be selected so that theamount of oxygen is not sufficient to completely oxidize the zinc toform zinc oxide. The amount of oxidation of zinc may affect thetransmittance. For example, completely oxidized zinc may have atransmittance of greater than about 80 percent. One manner ofdetermining the desired oxygen flow is to run a reactive sputteringprocess using argon and oxygen gases without using nitrogen gas.Experiments may be performed at different oxygen flow rates and theoptical transmittance in the visible wavelength may be measured. Thedesired oxygen flow may be just before the film has a maximumtransparency that may be achieved. Table I shows the opticaltransmittance for zinc oxide reactively sputter deposited at variousoxygen flow rates. In one embodiment, the maximum preferredtransmittance may be 80 percent. In other embodiments, the maximumtransmittance may not be 80 percent if the glass absorption or lightinterference is included. The experiments may be useful when usingdifferent DC target power, different substrate temperature, or evendifferent oxygen containing gases such as N₂O.

TABLE I Oxygen Flow Rate Transmittance (sccm/m³) (%) 0 <5 50 <5 100 <5125 82 150 85 200 90

Another method to determine the desired oxygen gas flow is to performthe reactive sputtering to form zinc oxide under the condition ofproviding no nitrogen or a low amount of nitrogen as discussed above andthen measure the sheet resistance. An oxygen flow rate that produces asheet resistance between about 100 ohm/sq and 1.0×10⁷ ohm/sq may be thedesired oxygen flow rate.

Yet another manner for determining the desired oxygen flow rate is totake an XRD film structure measurement. FIGS. 2A-2E are XRD graphs forfilms showing the formation of zinc and zinc oxide peaks as a functionof oxygen gas flow. Each of the films shown in FIGS. 2A-2E weredeposited at an argon flow rate of 600 sccm/m³ and 1,000 W and variousoxygen flow rates.

FIG. 2A shows an XRD graph of a film formed when no oxygen gas isprovided during the sputtering. Several zinc peaks were produced havingvarious intensities. A zinc (002) peak is shown for 2 theta (i.e., theangle between the incident x-ray and the detector of the diffractometer)between about 35.5 and 37 with an intensity of about 625 counts. A zinc(100) peak is shown between about 38 and 40 with an intensity of about450 counts. A zinc (101) peak is shown between about 42.5 and 44 with anintensity of about 1050 counts. A zinc (102) peak is shown between about53 and 55 with an intensity of about 325 counts. A zinc (103) peak isshown between about 69.5 and 70 with an intensity of about 300. A zincpeak (110) peak is shown between about 70 and 71 with an intensity ofabout 275 counts. The ratio of peak heights for the zinc (002):zinc(100):zinc (101):zinc (102):zinc (103):zinc (110) is about2.27:1.64:3.82:1.182:1.091:1. All peaks are marked using theInternational Center for Diffraction Data (ICDD) PDF2 database (rev.2004) for phase identification.

When oxygen gas is provided at a flow rate of 50 sccm/m³, the zinc peaksdiminish in intensity as shown in FIG. 2B. The zinc (002) peakdiminishes to about 500 counts. The zinc (100) peak diminishes to about375 counts. The zinc (101) peak diminishes to about 750 counts. The zinc(102) peak diminishes to about 250 counts. The zinc (110) peakdiminishes to about 225 counts, and the zinc (103) peak is not present.The ratio of the peak heights for zinc (002):zinc (100):zinc (101):zinc(102):zinc (110) is about 2.22:1.67:3.33:1.11:1.

When the oxygen gas is provided at a flow rate of 100 sccm/m³, all ofthe zinc peaks disappear except the zinc (101) peak which has diminishedto about 375 counts as shown in FIG. 2C. When the oxygen gas is providedat 150 sccm/m³, the zinc peaks are completely gone, but a zinc oxide(002) peak appears between about 33.5 and 35 with an intensity of about950 counts as shown in FIG. 2D. When the oxygen flow rate is increasedto 200 sccm/m³, the zinc oxide (002) peak increases in intensity toabout 1,000 counts as shown in FIG. 2E.

The amount of oxygen supplied, according to the XRD data, should be lessthan about 150 sccm/m³ because at 150 sccm/m³ a strong zinc oxide peakappears. It is to be understood that the flow rate of oxygen isproportional to the chamber size. Thus, for as the size of the chamberincreases, the oxygen flow rate may also increase. Similarly, as thesize of the chamber is reduced, the oxygen flow rate may decrease.

To determine the desired nitrogen flow rate, XRD film structuremeasurements may be taken. FIGS. 3A-3F are XRD graphs for showing theformation of a semiconductor film according at various nitrogen gas flowrates according to one embodiment of the invention. Each of the filmsshown in FIGS. 3A-3F were deposited at an argon flow rate of 600sccm/m³, 2,000 W, an oxygen flow rate of 100 sccm/m³, and variousnitrogen flow rates.

FIG. 3A shows an XRD graph of a film deposited with no nitrogen. Thegraph reveals several strong peaks including a peak between about 35 andabout 37 of zinc oxide (101) and zinc (002) having an intensity of about575 counts, a peak between about 38 and 40 of zinc (100) having anintensity of about 380 counts, and a peak between about 42.5 and 44 ofzinc (101) having an intensity of about 700 counts. Smaller peaks ofzinc oxide (002) between about 35.5 and 37 with an intensity of about390 counts, zinc (102) between about 53 and 55 with an intensity ofabout 275 counts, zinc (103) between about 69.5 and 70 with an intensityof about 225 counts, and a peak of zinc (110) between about 70 and 71with an intensity of about 225 counts are also present. The ratio of thepeak heights for zinc oxide (101):zinc (002):zinc (100):zinc (101):zincoxide (002):zinc (102):zinc (103):zinc (110) is about2.55:2.55:1.24:3.11:1.73:1.22:1:1.

When nitrogen is provided during the reactive sputtering at a flow rateof 300 sccm/m³, the zinc the zinc oxide peaks have significantlydiminished to the point where zinc oxide may no longer be present asshown in FIG. 3B. When the nitrogen flow rate is increased to 500sccm/m³, all of the zinc and zinc oxide peaks have diminished and thefilm has an amorphous structure as shown in FIG. 3C.

When the nitrogen flow rate is increased to 1,000 sccm/m³, two new peaksappear as shown in FIG. 3D. A first peak of Zn₃N₂ (222) has formedbetween about 31 and 33 with an intensity of about 2050 counts. A secondpeak of Zn₃N₂ (411) has formed between about 35 and 42 with an intensityof about 1850 counts. The ratio of peak heights for Zn₃N₂ (222):Zn₃N₂(411) is about 1.11:1. When the nitrogen gas flow rate is increased to1,250 sccm/m³, the Zn₃N₂ (222) peak intensifies to about 2500 counts andthe Zn₃N₂ (411) peak intensifies to about 2600 counts as shown in FIG.3E. The ratio of peak heights for Zn₃N₂ (222):Zn₃N₂ (411) is about0.96:1. When the nitrogen flow rate is increased to 2,500 sccm/m³, theZn₃N₂ (222) peak and the Zn₃N₂ (411) weaken to about 2350 and 2050respectively, but a new peak of Zn₃N₂ (400) develops between about 36and 37.5 with an intensity of about 1700 counts as shown in FIG. 3F. Theratio of peak heights for Zn₃N₂ (222):Zn₃N₂ (411):Zn₃N₂ (400) is about1.38:1.21:1.

The amount of nitrogen supplied, according to the XRD data, should begreater less than about 300 sccm/m³ because at 300 sccm/m³ the zincoxide peaks diminish significantly such that essentially no zinc oxideis present in the film. It is to be understood that the flow rate ofnitrogen is proportional to the chamber size. Thus, for as the size ofthe chamber increases, the nitrogen flow rate may also increase.Similarly, as the size of the chamber is reduced, the nitrogen flow ratemay decrease.

Therefore, combining the oxygen flow rates from above and the nitrogenflow rates from above, the new semiconductor film discussed herein maybe deposited under a nitrogen to oxygen flow rate ratio of greater thanabout 2:1. In one embodiment, the flow ratio of nitrogen to oxygen maybe 10:1 to about 50:1. In still another embodiment, the flow ratio ofnitrogen to oxygen may be 20:1.

To produce the semiconductor material, the flow rate of the nitrogencontaining gas may be much greater than the flow rate of the oxygencontaining gas as discussed above. The deposited semiconductor materialmay have a mobility greater than amorphous silicon. Table II shows themobility as a function of nitrogen gas flow rate according to oneembodiment of the invention.

TABLE II Nitrogen Oxygen Flow Rate Flow Rate Mobility (sccm/m³)(sccm/m³) (cm²/V-s) 500 50 1 100 13.5 250 5 1,000 50 14 100 27 1,500 0<1 25 8 50 31 150 23.5 200 1 250 2 2,000 0 1 50 34 100 29 2,500 0 2.5 2515 50 33.5 100 33 150 25 200 10 250 12

Films deposited under conditions of 0 sccm oxygen had mobility of lessthan 5 cm²/V-s for all flow rates of nitrogen gas. Films deposited underconditions of 25 sccm/m³ oxygen had a mobility of about 8 cm²/V-s for anitrogen flow rate of 1,500 sccm/m³ and about 15 cm²/V-s for a nitrogenflow rate of 2,500 sccm/m³. Films deposited under conditions of 200sccm/m³ oxygen had a mobility of about 1 cm²/V-s for a nitrogen flowrate of 1,500 sccm/m³ and a mobility of about 10 cm²/V-s for a nitrogenflow rate of 2,500 sccm/m³. Films deposited under conditions of 250sccm/m³ oxygen has a mobility of about 5 cm²/V-s for a nitrogen flowrate of 500 sccm/m³, about 2 cm²/V-s for a nitrogen flow rate of 1,500sccm/m³, and about 12 cm²/V-s for a nitrogen flow rate of 2,500 sccm/m³.

For films deposited with an oxygen flow rate of between 50 sccm/m³ and150 sccm/m³, the mobility of the films was markedly increased over thefilms deposited at oxygen flow rates of 25 sccm/m³ and below and filmsdeposited at oxygen flow rates of 200 sccm/m³ and above. Additionally,the films deposited with an oxygen flow rate of between 50 sccm/m³ and150 sccm/m³ have mobilities far greater than amorphous silicon. Atnitrogen flow rates of between 1,000 sccm/m³ and 2,500 sccm/m³, themobility of the films were, in most cases, higher than 22 cm²/V-s. Whencompared to amorphous silicon, which has a mobility of about 1 cm²/V-s,the semiconductor films containing zinc, oxygen, and nitrogen have asignificant improvement in mobility. Hence, nitrogen to oxygen gas flowratios of about 10:1 to about 50:1 may produce semiconductor filmshaving mobility greater than 20 times the mobility of amorphous siliconand 2 times the mobility of polysilicon. It is to be understood thatwhile the table shows specific flow rates of nitrogen gas and oxygengas, the flow rates of the oxygen gas and nitrogen gas are relative tothe chamber size and thus, are scalable to account for different chambersizes.

Table III shows the sheet resistance, carrier concentration, andresistivity as a function of nitrogen gas flow rate according to oneembodiment of the invention. For flow ratios of nitrogen gas to oxygengas between about 10:1 to about 50:1, the sheet resistance of thesemiconductor layer comprising zinc, oxygen, and nitrogen may be betweenabout 100 ohm/sq and about 10,000 ohm/sq. With an increase in bothnitrogen flow rate and oxygen flow rate, the electron carrierconcentration lowers. Consequently, the resistivity increases.

TABLE III Nitrogen Oxygen Sheet Carrier Flow Rate Flow Rate ResistanceConcentration Resistivity (sccm/m³) (sccm/m³) (ohm-cm) (#/cc) (ohm-cm)500 50 400 1.00E+21 0.009 100 800 5.00E+19 0.012 1,000 50 750 5.00E+190.012 100 5000 4.00E+18 0.1 1,500 0 600 4.00E+21 0.014 50 950 9.00E+180.014 2,000 0 1000 9.00E+20 0.014 50 2000 5.00E+18 0.017 100 90002.00E+18 0.1 2,500 0 6000 2.00E+19 0.11 50 5000 4.00E+18 0.09 100 90001.50E+18 0.12

Annealing may also significantly raise the mobility of the semiconductorfilm containing zinc, oxygen, and nitrogen. Table IV shows the mobilityas a function of nitrogen gas flow rate after annealing according to oneembodiment of the invention. After annealing, the mobility may begreater than 90 cm²/V-s. The annealing may occur for about five minutesin a nitrogen atmosphere at a temperature of about 400 degrees Celsius.

TABLE IV Nitrogen Oxygen Flow Rate Flow Rate Mobility (sccm/m³)(sccm/m³) (cm²/V-s) 500 0 1 50 13.5 100 5 1,000 0 28 50 48 100 15 1,2500 29 100 20 1,500 50 94 2,000 50 92 2,500 0 50 50 65 100 21

The amount of dopant may also affect the mobility of the semiconductorfilm containing zinc, nitrogen, and oxygen. Table V shows the mobility,sheet resistance, carrier concentration, and resistivity for variousnitrogen flow rates when reactively sputtering a zinc sputtering targetthat is doped with 1.0 weight percent aluminum or 1.5 weight percentaluminum.

TABLE V Nitrogen Sheet Carrier Percent Flow Rate Mobility ResistanceConcentration Resistivity Dopant (sccm/m³) (cm²/V-s) (ohm-cm) (#/cc)(ohm-cm) 1.0 100 0.0 900 1.00E+21 0.03 200 5.8 6,000 1.00E+19 0.10 30011.0 99,000 5.00E+17 1.00 400 10.5 110,000 4.00E+17 3.00 1.5 0 0.0 1508.00E+21 0.01 100 0.0 1,200 7.00E+20 0.09 200 9.0 11,000 2.00E+18 0.80300 9.1 110,000 2.50E+17 5.00

The temperature of the susceptor may also influence the mobility of thesemiconductor film. Table VI shows the mobility, sheet resistance,carrier concentration, and resistivity for various nitrogen flow ratesin sputtering a zinc sputtering target at temperatures of 30 degreesCelsius, 50 degrees Celsius, and 95 degrees Celsius. As may be seen fromTable VI, the reactive sputtering may effectively form a semiconductorfilm having mobility higher than amorphous silicon and polysilicon attemperatures significantly below 400 degrees Celsius, includingtemperatures approaching room temperature. Thus, even without annealing,the semiconductor film may have a higher mobility than amorphoussilicon.

TABLE VI Carrier Nitrogen Susceptor Sheet Concen- Flow Rate TemperatureMobility Resistance tration Resistivity (sccm/m³) (Celsius) (cm²/V-s)(ohm-cm) (#/cc) (ohm-cm) 500 30 1.0 200 1.00E+21 0.009 50 1.5 2102.00E+19 0.008 95 2.0 300 4.00E+18 0.014 1,500 30 15.0 1,100 1.00E+210.030 50 31.0 950 9.00E+18 0.029 95 17.0 850 4.00E+18 0.028 2,500 3028.0 3,100 7.00E+20 0.900 50 33.0 3,100 2.00E+19 0.078 95 32.0 2,9504.00E+18 0.077

While the power may be described herein as specific values, it is to beunderstood that the power applied to the sputtering target isproportional to the area of the target. Hence, power values betweenabout 10 W/cm² to about 100 W/cm² will generally achieve the desiredresults. Table VII shows the affect of the applied DC power on themobility, carrier concentration, and resistivity for nitrogen gas flowsof 1,500 sccm/m³ and 2,500 sccm/m³. Power levels between about 1,000 Wand 2,000 W produce semiconductor films having a mobility significantlyhigher than amorphous silicon.

TABLE VII Nitrogen Carrier Flow Rate Power Mobility ConcentrationResistivity (sccm/m³) (W) (cm²/V-s) (#/cc) (ohm-cm) 1,500 1,000 345.00E+17 0.80 1,500 41 3.10E+18 0.08 2,000 31 7.20E+18 0.05 2,500 1,00030 4.00E+17 2.00 1,500 39 1.50E+18 0.10 2,000 34 2.50E+18 0.09

The film deposited according to the above discussed depositiontechniques may comprise a ternary compound semiconductor material havingzinc, nitrogen, and oxygen such as ZnN_(x)O_(y). In one embodiment, theternary compound semiconductor material may be doped such asZnN_(x)O_(y):Al. The ternary semiconductor compound may have a highmobility and a low electron carrier density when deposited at roomtemperature in contrast to zinc oxide which has a high electron mobilityand a high electron carrier density. In one embodiment, the ternarycompound has a mobility higher than 30 cm²/V-cm and an electron carrierdensity lower than 1.0e+19 #/cc. When the film is annealed at about 400degrees Celsius, the mobility may be increased to greater than 100cm²/V-cm and the electron carrier density may be lower than 1.0e+18 #/ccwithout changing the film crystallographic orientation and composition.The high mobility and low electron density may be achieved for theternary compound even when the film is an amorphous compound or poorlyoriented crystallographic compound.

The optical band gap of the ternary compound may also be improvedcompared to zinc oxide. Zinc oxide typically has a band gap of about 3.2eV. The ternary compound comprising zinc, nitrogen, and oxygen, on theother hand, may have a band gap from about 3.1 eV to about 1.2 eV. Theband gap may be adjusted by altering the deposition parameters such asnitrogen to oxygen flow ratio, power density, pressure, annealing, anddeposition temperature. Due to the lower band gap, the ternary compoundmay be useful for photovoltaic devices and other electronic devices. Atvery high processing temperatures such as 600 degrees Celsius, theternary film may be converted to p-type or n-type semiconductormaterial. The annealing or plasma treatment may be fine tuned withoutfundamentally changing the compound structure and chemical composition.The fine tuning permits the properties of the compound to be tailored tomeet the performance requirements of devices in which the compound maybe used.

The ternary compound may be useful as a transparent semiconductor layerin a thin film transistor (TFT) device, a compound layer in aphotovoltaic device or solar panel, or as a compound layer in a sensordevice. The ternary compound is very stable. Table VIII below shows theatomic composition of a structure having the ternary compound of thepresent invention as deposited over a silicon oxide layer and a glasssubstrate. The ternary compound was sputter deposited in an atmosphereof oxygen, argon, and nitrogen using an aluminum doped zinc sputteringtarget. Table VIII shows the atomic composition results of the structuredeposited at a flow ratio of oxygen to argon to nitrogen of 1:12:30 anda temperature of 50 degrees Celsius. Table IX shows the same film oneweek after deposition. Table X shows the same film two weeks afterdeposition.

TABLE VIII Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 018.0 4.0 1.2 0.0 42.6 0.1 0.0 34.1 25 0.3 5.9 0.0 2.7 19.3 1.3 0.2 70.350 0.0 5.2 0.0 3.3 18.9 2.1 0.5 70.1 75 0.0 5.1 0.0 3.9 20.5 3.0 0.367.2 100 0.1 5.0 0.0 4.0 20.2 3.0 0.2 67.6 125 0.9 4.6 0.0 3.7 20.7 3.30.0 66.8 150 0.8 4.9 0.0 4.3 21.0 3.1 0.2 65.8 175 0.4 4.8 0.0 4.0 21.13.3 0.2 66.2 200 0.0 5.0 0.0 4.3 21.3 3.3 0.5 65.6 225 0.0 5.0 0.0 4.221.5 3.5 0.0 65.8 250 0.7 4.0 0.0 3.6 22.4 3.4 0.0 66.0 275 0.0 5.2 0.04.4 21.1 3.3 0.0 66.0 300 0.0 5.4 0.0 4.4 21.2 3.7 0.1 65.2 325 0.0 5.20.0 4.5 21.6 3.6 0.2 65.0 350 0.7 5.2 0.0 4.4 21.5 3.9 0.3 64.1 375 0.05.2 0.0 4.5 21.1 3.6 0.1 65.6 400 0.3 5.3 0.0 4.7 20.8 3.8 0.0 64.9 4250.6 5.2 0.0 4.5 21.7 3.8 0.0 64.2 450 0.4 5.0 0.0 4.4 22.8 3.8 0.3 63.3475 0.5 5.3 0.0 4.5 22.5 3.6 0.0 63.7 500 0.3 5.5 0.0 4.6 22.2 3.8 0.063.6 525 0.3 5.1 0.0 4.3 23.3 3.5 0.0 63.5 550 0.5 5.3 0.0 4.5 23.2 3.80.0 62.7 575 0.5 5.1 0.0 4.3 22.8 3.5 0.1 63.6 600 0.0 5.1 0.0 4.4 23.53.6 0.0 63.5 625 0.0 5.3 0.0 4.4 23.8 3.5 0.1 63.0 650 0.0 5.2 0.0 4.124.5 3.6 0.0 62.6 675 0.0 5.3 0.0 4.5 23.9 3.3 0.0 63.0 700 0.1 5.1 0.04.1 24.0 3.3 0.7 62.6 725 0.0 5.2 0.0 4.1 25.0 3.0 0.0 62.6 750 0.0 5.20.0 3.8 25.4 3.1 0.0 62.5 775 0.1 5.1 0.0 3.7 25.2 2.6 0.0 63.2 800 0.34.9 0.0 2.8 28.0 2.6 0.5 60.9 825 1.0 3.5 0.0 1.3 41.4 2.3 3.3 47.2 8500.4 1.8 0.0 0.5 56.2 1.4 16.6 23.1 875 0.5 0.9 0.1 0.3 62.5 0.8 24.210.7 900 0.9 0.5 0.2 0.2 64.7 0.4 28.1 5.1 925 0.2 0.4 0.1 0.0 66.6 0.330.2 2.3 950 0.0 0.2 0.1 0.0 67.3 0.2 31.3 0.9 975 0.1 0.1 0.1 0.0 67.40.1 31.7 0.6 1000 0.4 0.1 0.1 0.1 66.8 0.1 32.2 0.3 1025 0.0 0.2 0.1 0.067.2 0.1 32.1 0.4 1050 0.4 0.1 0.2 0.0 67.0 0.0 32.0 0.4 1075 0.3 0.00.1 0.0 67.1 0.0 32.2 0.3 1100 0.0 0.0 0.1 0.0 67.4 0.0 32.1 0.4 11250.0 0.0 0.2 0.2 67.2 0.0 32.3 0.1 1150 0.5 0.0 0.1 0.1 67.1 0.0 32.1 0.21175 0.0 0.0 0.1 0.0 67.2 0.0 32.6 0.2 1200 0.4 0.2 0.1 0.0 66.9 0.032.1 0.3 1225 0.1 0.2 0.0 0.0 67.1 0.0 32.4 0.2 1250 0.0 0.2 0.0 0.067.2 0.0 32.4 0.3

TABLE IX Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 32.51.6 1.5 0.0 40.9 0.2 0.0 23.4 25 0.5 4.5 0.0 2.7 20.2 1.2 0.1 70.8 500.0 5.3 0.0 3.6 17.7 1.9 0.9 70.6 75 0.6 5.6 0.0 4.1 18.2 2.7 0.5 68.5100 0.2 5.2 0.0 3.7 18.8 3.2 0.0 68.9 125 0.8 5.5 0.0 4.2 17.6 3.5 0.168.3 150 0.5 5.2 0.0 3.9 19.0 3.2 0.3 67.9 175 0.7 5.1 0.0 4.3 18.7 3.40.0 67.8 200 0.0 5.2 0.0 4.2 19.5 3.7 0.2 67.4 225 0.0 5.5 0.0 4.4 18.43.7 0.2 67.9 250 0.8 5.4 0.0 4.2 18.5 3.5 0.0 67.6 275 0.5 5.4 0.0 4.419.3 3.8 0.6 66.1 300 0.0 5.2 0.0 4.2 20.3 3.6 0.1 66.7 325 0.4 5.6 0.04.1 20.2 3.6 0.3 65.9 350 0.7 5.5 0.0 4.2 19.8 4.0 0.5 65.4 375 0.1 5.80.0 4.2 19.7 3.8 0.5 66.0 400 0.3 5.5 0.0 4.2 20.7 3.9 0.0 65.4 425 0.06.1 0.0 4.7 20.2 3.9 0.0 65.2 450 0.0 5.3 0.0 4.0 20.6 3.9 0.3 65.8 4750.0 5.8 0.0 4.4 20.6 3.9 0.0 65.3 500 0.1 5.5 0.0 4.4 21.5 3.8 0.1 64.6525 0.5 5.6 0.0 4.4 20.9 3.7 0.0 64.8 550 0.0 5.7 0.0 4.3 21.5 3.9 0.064.7 575 0.0 5.7 0.0 4.6 22.5 3.6 0.1 63.5 600 0.0 5.8 0.0 4.1 23.1 3.40.2 63.3 625 0.0 5.4 0.0 4.1 22.8 3.4 0.8 63.6 650 0.4 5.2 0.0 3.9 23.03.7 0.0 63.8 675 0.8 5.4 0.0 4.0 23.2 3.3 0.4 62.8 700 0.4 5.6 0.2 4.023.3 3.4 0.0 63.1 725 0.0 5.5 0.0 3.9 24.3 3.4 0.0 62.9 750 0.0 5.6 0.04.0 24.1 3.1 0.2 63.0 775 0.4 5.4 0.0 3.6 24.1 3.0 0.2 63.4 800 0.3 5.00.0 3.0 26.1 2.9 0.3 62.5 825 0.0 3.4 0.6 1.6 36.2 2.5 4.5 51.2 850 0.11.6 0.3 0.8 52.1 1.7 16.3 27.2 875 0.1 1.1 0.1 0.4 60.6 0.9 24.0 12.6900 0.6 0.3 0.1 0.1 65.1 0.5 27.5 6.0 925 0.0 0.0 0.2 0.1 67.0 0.3 29.62.8 950 0.2 0.0 0.2 0.0 67.8 0.2 30.7 0.9 975 0.0 0.0 0.3 0.1 67.9 0.131.2 0.4 1000 0.0 0.0 0.1 0.0 67.5 0.1 32.0 0.2 1025 0.2 0.0 0.0 0.068.1 0.0 31.5 0.2 1050 0.0 0.0 0.0 0.0 67.8 0.0 31.9 0.2 1075 0.1 0.00.0 0.0 67.6 0.1 32.2 0.0 1100 0.6 0.0 0.1 0.0 67.2 0.1 31.8 0.2 11250.1 0.0 0.0 0.0 68.1 0.0 31.7 0.1 1150 0.3 0.0 0.1 0.0 67.8 0.0 31.7 0.21175 0.4 0.0 0.1 0.0 67.9 0.0 31.5 0.1 1200 0.0 0.0 0.0 0.0 68.0 0.131.8 0.1 1225 0.3 0.0 0.1 0.0 67.8 0.0 31.6 0.1 1250 0.1 0.0 0.0 0.068.2 0.1 31.6 0.0 1275 0.0 0.0 0.0 0.0 68.3 0.0 31.6 0.0 1300 0.0 0.00.0 0.0 68.2 0.1 31.7 0.1 1325 0.0 0.0 0.0 0.0 68.4 0.0 31.5 0.1 13500.2 0.0 0.0 0.0 68.2 0.0 31.5 0.0 1375 0.1 0.0 0.0 0.0 67.9 0.1 31.7 0.11400 0.0 0.1 0.1 0.0 68.1 0.0 31.6 0.1 1425 0.2 0.0 0.0 0.0 68.3 0.031.4 0.1 1450 0.1 0.0 0.1 0.0 68.1 0.1 31.3 0.3 1475 0.1 0.0 0.0 0.068.6 0.1 31.1 0.1 1500 0.0 0.1 0.1 0.0 68.4 0.1 31.3 0.0

TABLE X Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 16.80.3 2.1 0.0 47.8 0.2 0.0 32.8 25 0.4 1.8 1.5 0.9 35.8 0.7 0.0 58.9 500.6 3.6 0.6 2.0 26.5 1.0 0.0 65.7 75 0.0 4.8 0.0 3.1 19.6 1.4 0.5 70.6100 1.0 5.5 0.0 3.6 17.9 2.5 0.0 69.4 125 0.6 5.5 0.0 3.5 18.9 2.8 0.468.4 150 1.0 5.1 0.0 3.6 19.1 3.1 0.0 68.0 175 1.3 5.3 0.0 4.2 19.5 3.30.0 66.4 200 1.4 5.3 0.0 4.1 19.1 3.5 0.1 66.6 225 0.2 5.2 0.0 3.9 20.13.4 0.0 67.2 250 0.4 5.4 0.0 4.1 19.6 3.3 0.0 67.2 275 0.2 5.5 0.0 4.220.4 3.6 0.3 65.8 300 0.9 5.3 0.0 4.2 20.5 3.3 0.0 65.8 325 0.6 5.1 0.04.1 21.1 3.3 0.3 65.5 350 0.2 5.4 0.0 4.2 20.4 3.5 0.0 66.3 375 0.4 5.70.0 4.3 19.4 3.8 0.1 66.2 400 0.3 5.6 0.1 4.4 20.6 3.6 0.3 65.1 425 0.05.7 0.0 4.4 20.8 3.6 0.2 65.4 450 1.2 6.0 0.0 4.5 20.6 3.5 0.2 64.0 4750.0 5.9 0.0 4.3 20.9 3.7 0.1 65.1 500 0.0 5.9 0.0 4.2 19.9 3.8 0.4 65.9525 0.0 5.6 0.2 4.2 22.4 3.6 0.0 64.0 550 1.7 6.0 0.0 4.2 20.7 3.7 0.063.8 575 0.1 5.9 0.0 4.3 21.3 3.6 0.2 64.6 600 0.0 5.8 0.0 4.4 21.8 3.50.0 64.4 625 0.2 5.5 0.0 3.8 24.8 3.4 0.1 62.2 650 0.7 5.7 0.0 4.4 23.13.4 0.2 62.6 675 0.0 5.8 0.0 4.3 22.6 3.3 0.0 64.0 700 0.6 5.3 0.0 3.922.8 3.1 0.0 64.3 725 0.3 5.5 0.0 3.7 24.7 3.2 0.0 62.5 750 0.0 5.2 0.03.7 25.1 3.0 0.2 62.9 775 0.9 5.3 0.0 3.6 24.8 2.9 0.0 62.6 800 0.0 5.30.0 2.8 26.5 2.9 1.0 61.5 825 1.0 4.0 0.0 1.5 36.7 2.1 5.3 49.5 850 0.52.4 0.0 0.8 50.0 1.7 14.5 30.2 875 0.7 1.6 0.0 0.4 58.4 0.9 22.4 15.7900 0.6 1.1 0.0 0.2 63.0 0.5 26.5 8.1 925 0.2 0.6 0.2 0.1 65.8 0.3 28.64.2 950 0.1 0.2 0.3 0.0 66.9 0.1 30.5 2.1 975 0.4 0.4 0.1 0.0 66.9 0.130.9 1.2 1000 0.3 0.0 0.3 0.0 67.6 0.0 31.4 0.5 1025 0.1 0.0 0.3 0.167.5 0.0 31.7 0.4 1050 0.1 0.0 0.3 0.1 67.5 0.1 31.7 0.3 1075 0.2 0.00.3 0.0 67.5 0.0 31.7 0.2 1100 0.2 0.0 0.3 0.1 67.5 0.0 31.8 0.2 11250.6 0.0 0.2 0.0 67.5 0.0 31.4 0.3 1150 0.5 0.0 0.3 0.0 67.3 0.0 31.5 0.31175 0.1 0.0 0.2 0.0 67.6 0.0 31.9 0.2 1200 0.2 0.0 0.3 0.0 67.3 0.032.0 0.2 1225 0.3 0.0 0.3 0.0 67.1 0.0 31.9 0.3 1250 0.2 0.0 0.2 0.067.3 0.0 32.0 0.3 1275 0.2 0.0 0.2 0.0 67.5 0.1 31.6 0.3 1300 0.2 0.00.1 0.0 67.4 0.1 31.9 0.3 1325 0.2 0.0 0.2 0.0 67.5 0.0 32.1 0.2 13500.0 0.0 0.2 0.0 67.5 0.0 32.1 0.2 1375 0.2 0.2 0.2 0.0 67.7 0.0 31.5 0.21400 0.1 0.0 0.3 0.0 67.1 0.1 32.0 0.4 1425 0.0 0.2 0.2 0.1 67.7 0.031.6 0.3 1450 0.2 0.0 0.3 0.1 67.4 0.0 31.8 0.2 1475 0.0 0.0 0.3 0.067.6 0.0 31.9 0.2 1500 0.0 0.0 0.3 0.0 67.5 0.0 32.0 0.2 1525 0.0 0.00.3 0.0 67.9 0.0 31.6 0.2 1550 0.5 0.1 0.3 0.0 67.5 0.0 31.3 0.2 15750.2 0.1 0.3 0.0 67.6 0.0 31.5 0.3 1600 0.3 0.1 0.3 0.1 67.5 0.0 31.5 0.21625 0.0 0.0 0.3 0.0 67.6 0.0 31.8 0.3 1650 0.0 0.0 0.3 0.0 67.5 0.031.8 0.3 1675 0.2 0.0 0.3 0.0 67.6 0.0 31.6 0.3 1700 0.7 0.1 0.3 0.067.2 0.0 31.5 0.3 1725 0.0 0.1 0.2 0.0 67.8 0.0 31.6 0.3 1750 0.2 0.00.2 0.0 67.5 0.0 31.7 0.4 1775 0.1 0.0 0.3 0.0 67.1 0.0 32.3 0.3 18000.0 0.0 0.2 0.0 67.8 0.1 31.7 0.3 1825 0.4 0.0 0.2 0.0 67.4 0.0 31.8 0.21850 0.3 0.0 0.3 0.1 67.6 0.0 31.5 0.3 1875 0.5 0.0 0.2 0.0 67.2 0.031.8 0.3

As may be seen from Tables VIII, IX, and X, the ternary compound wasdeposited as a film with a thickness of about 850 Angstroms. A naturalpassivation layer may form to a depth of about 25 Angstroms on top ofthe ternary compound layer. Thereafter, the layer maintained a zincconcentration of about 62 atomic percent to about 71 atomic percent, anoxygen concentration of about 18 atomic percent to about 26 atomicpercent, a nitride concentration of about 4.0 atomic percent to about6.1 atomic percent, and a nitrite concentration of about 2.7 atomicpercent to about 4.7 atomic percent for two weeks.

When the film is annealed, the composition of the film remainssubstantially the same as the non-annealed film. Tables XI, XII, andXIII show the composition of the annealed ternary compound of TablesVIII, IX, and X respectively.

TABLE XI Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 19.75.8 2.1 0.1 35.2 0.7 0.0 36.5 25 0.0 6.0 0.1 3.0 22.2 1.8 0.0 67.0 500.0 6.0 0.0 3.6 20.3 2.4 0.4 67.4 75 0.0 6.3 0.0 3.9 19.3 3.1 0.0 67.5100 0.0 6.0 0.0 3.9 18.8 3.4 0.0 67.9 125 0.2 5.7 0.0 4.0 18.9 3.3 0.667.4 150 0.0 5.8 0.0 4.0 19.9 3.4 0.1 66.9 175 0.0 5.8 0.0 4.8 18.4 3.40.6 67.1 200 0.0 5.6 0.0 4.5 20.5 3.3 0.4 65.7 225 0.0 5.7 0.0 4.9 19.43.3 0.4 66.4 250 1.0 5.5 0.0 4.6 18.8 4.0 0.0 66.1 275 0.0 5.4 0.0 4.519.6 3.9 0.6 65.9 300 0.3 5.8 0.0 4.7 20.3 3.9 0.0 65.0 325 0.0 5.8 0.04.7 20.7 3.7 0.0 65.1 350 0.3 5.8 0.0 4.6 21.3 3.9 0.1 64.1 375 0.0 5.90.0 4.7 21.0 4.0 0.1 64.3 400 1.3 5.8 0.0 4.7 21.2 4.1 0.0 62.9 425 0.05.9 0.0 4.8 21.3 3.9 0.5 63.7 450 0.0 6.0 0.0 4.9 20.1 4.2 0.0 64.8 4751.0 5.9 0.0 4.8 20.9 3.9 0.0 63.6 500 0.6 5.8 0.0 4.7 22.1 4.0 0.8 62.0525 0.4 5.9 0.0 4.7 21.8 4.0 0.5 62.7 550 0.0 5.9 0.0 4.8 21.8 4.1 0.263.3 575 0.1 5.9 0.0 4.7 22.5 4.1 0.0 62.7 600 0.0 5.9 0.0 4.6 22.5 4.10.0 62.9 625 0.0 5.8 0.0 4.5 23.4 3.8 0.0 62.4 650 0.1 5.7 0.0 4.8 22.03.9 0.3 63.3 675 0.2 5.7 0.0 4.6 23.4 3.7 0.2 62.2 700 0.3 5.7 0.0 4.623.9 3.7 0.1 61.8 725 0.3 5.5 0.0 4.3 24.5 3.5 0.4 61.6 750 0.0 5.3 0.04.3 24.4 3.3 0.0 62.6 775 0.2 4.8 0.0 3.8 26.2 2.9 0.8 61.3 800 0.7 3.10.6 1.9 35.9 2.6 2.9 52.3 825 0.3 1.3 0.6 0.8 52.3 1.9 14.9 28.0 850 0.00.6 0.4 0.3 60.9 0.8 23.9 13.2 875 0.2 0.4 0.3 0.3 64.7 0.7 27.1 6.5 9000.0 0.1 0.1 0.0 66.8 0.4 29.6 3.1 925 0.3 0.1 0.1 0.0 67.2 0.2 30.9 1.2950 0.0 0.0 0.1 0.0 68.2 0.1 31.0 0.7 975 0.2 0.0 0.0 0.0 67.5 0.0 31.70.5 1000 0.0 0.0 0.0 0.0 67.7 0.1 31.8 0.3 1025 0.5 0.0 0.0 0.0 67.4 0.031.7 0.4 1050 0.1 0.1 0.0 0.0 67.9 0.0 31.6 0.3 1075 0.0 0.1 0.0 0.067.8 0.0 31.9 0.2 1100 0.0 0.0 0.0 0.0 67.8 0.0 31.9 0.3 1125 0.0 0.10.0 0.0 67.4 0.1 32.2 0.3 1150 0.0 0.0 0.1 0.0 68.0 0.0 31.7 0.2 11750.0 0.0 0.0 0.0 67.9 0.1 31.9 0.2 1200 0.3 0.1 0.0 0.0 67.1 0.0 32.1 0.41225 0.0 0.0 0.0 0.0 67.7 0.1 32.0 0.2 1250 0.2 0.0 0.0 0.0 67.6 0.032.0 0.2

TABLE XII Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 33.24.2 2.4 0.1 34.2 0.4 0.4 25.0 25 0.1 6.1 0.2 3.1 22.3 1.7 0.6 65.8 500.0 6.3 0.0 3.4 20.1 2.9 0.2 67.1 75 0.0 5.8 0.2 3.9 19.5 3.0 0.3 67.3100 0.0 6.0 0.0 4.0 19.2 3.0 0.2 67.6 125 0.0 5.6 0.2 4.0 19.5 3.3 0.267.3 150 0.1 5.7 0.1 4.3 20.4 3.3 0.4 65.9 175 0.1 6.1 0.1 4.4 19.8 3.50.8 65.3 200 0.0 6.1 0.0 4.2 20.1 3.8 0.3 65.6 225 1.1 5.8 0.0 4.6 20.03.2 0.4 64.9 250 1.1 5.5 0.0 4.2 20.8 3.9 0.0 64.6 275 0.8 5.5 0.1 4.320.2 3.8 0.2 65.1 300 0.1 5.6 0.0 4.7 20.3 3.9 0.2 65.4 325 0.6 5.7 0.04.3 20.4 4.1 0.1 65.0 350 0.0 5.8 0.0 4.7 21.0 4.1 0.0 64.4 375 0.4 5.70.0 4.3 21.7 4.2 0.3 63.6 400 0.0 5.6 0.0 4.3 21.1 4.4 0.0 64.5 425 0.05.9 0.1 4.5 21.8 4.2 0.0 63.5 450 0.4 6.0 0.0 4.4 21.8 4.2 0.0 63.2 4750.0 5.8 0.0 4.2 22.2 4.3 0.0 63.5 500 0.0 6.0 0.3 4.4 22.0 4.0 0.3 63.1525 0.4 5.8 0.0 4.6 23.2 4.0 0.2 61.9 550 0.0 5.5 0.1 4.2 22.2 4.1 0.064.0 575 0.7 5.7 0.2 4.2 22.6 4.1 0.0 62.5 600 0.0 5.7 0.0 3.8 23.3 3.70.0 63.4 625 0.7 5.8 0.0 3.9 23.2 4.0 0.4 62.1 650 0.0 5.6 0.0 3.9 24.13.8 0.0 62.6 675 0.0 5.7 0.0 3.9 24.1 3.7 0.0 62.7 700 0.1 5.7 0.2 4.123.5 3.6 0.0 62.9 725 0.0 5.0 0.2 3.9 24.5 3.4 0.0 63.1 750 0.0 5.4 0.23.8 25.0 3.2 0.0 62.4 775 0.1 5.2 0.0 3.4 25.1 3.2 0.1 63.0 800 0.8 4.80.0 2.5 28.7 2.9 1.1 59.2 825 1.0 2.9 0.0 1.1 42.5 2.2 7.9 42.4 850 0.41.1 0.4 0.4 55.6 1.4 20.0 20.7 875 0.3 0.5 0.5 0.2 62.2 0.9 25.8 9.6 9000.3 0.2 0.5 0.2 65.2 0.4 28.9 4.4 925 0.8 0.1 0.2 0.1 66.4 0.2 30.4 1.9950 0.0 0.0 0.1 0.0 67.3 0.2 31.6 0.7 975 0.1 0.0 0.3 0.1 67.3 0.0 31.90.3 1000 0.0 0.0 0.0 0.0 67.9 0.1 31.9 0.1 1025 0.2 0.0 0.1 0.0 67.7 0.031.8 0.2 1050 0.2 0.0 0.1 0.1 67.0 0.0 32.5 0.1 1075 0.7 0.0 0.1 0.067.0 0.1 32.0 0.0 1100 0.2 0.0 0.1 0.0 67.3 0.1 32.3 0.0 1125 0.6 0.00.1 0.0 66.8 0.1 32.4 0.0 1150 0.2 0.1 0.1 0.1 67.4 0.1 32.1 0.1 11750.2 0.0 0.0 0.0 67.6 0.0 32.2 0.0 1200 0.1 0.0 0.0 0.0 67.5 0.0 32.4 0.01225 0.0 0.0 0.0 0.0 67.4 0.0 32.6 0.0 1250 0.3 0.0 0.1 0.0 67.2 0.132.3 0.1 1275 0.3 0.1 0.1 0.0 67.0 0.1 32.5 0.1 1300 0.3 0.1 0.1 0.167.2 0.0 32.2 0.0 1325 0.5 0.0 0.1 0.0 67.2 0.0 32.1 0.0 1350 0.3 0.00.1 0.0 67.2 0.0 32.4 0.0 1375 0.2 0.0 0.0 0.0 67.2 0.0 32.5 0.1 14000.2 0.0 0.1 0.0 67.4 0.0 32.3 0.0 1425 0.2 0.0 0.1 0.0 67.5 0.0 32.2 0.11450 0.0 0.0 0.1 0.1 67.2 0.0 32.5 0.1 1475 0.2 0.0 0.1 0.0 67.3 0.032.4 0.0 1500 0.2 0.0 0.1 0.0 67.3 0.0 32.3 0.0

TABLE XIII Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 020.1 4.8 2.5 0.0 38.3 0.6 0.0 33.7 25 0.2 5.0 1.0 3.1 22.6 1.8 0.1 66.250 1.1 5.6 0.4 3.6 20.5 2.6 0.4 65.8 75 0.0 5.9 0.2 4.0 19.3 2.8 0.067.8 100 0.0 6.1 0.0 4.2 19.7 3.2 0.1 66.7 125 0.1 6.2 0.0 4.0 19.9 3.10.0 66.7 150 0.0 6.3 0.0 4.4 20.7 3.0 0.0 65.6 175 0.0 6.1 0.0 4.5 20.23.4 0.7 65.2 200 0.1 5.9 0.0 4.2 19.5 3.6 0.4 66.3 225 0.1 5.9 0.0 4.320.3 3.7 0.0 65.7 250 0.2 6.4 0.0 4.7 19.1 3.7 0.0 65.9 275 0.0 5.6 0.04.2 22.2 3.7 0.0 64.3 300 0.0 5.8 0.0 4.6 20.8 3.8 0.0 65.0 325 0.0 5.60.0 4.6 22.1 3.9 0.0 63.8 350 0.4 5.9 0.1 4.4 21.1 3.8 0.0 64.3 375 0.05.9 0.0 4.5 22.4 3.8 0.0 63.5 400 0.6 6.0 0.0 4.6 21.5 3.9 0.4 63.1 4250.0 5.6 0.1 4.5 20.5 4.1 0.0 65.3 450 0.3 5.8 0.1 4.3 22.5 3.6 0.0 63.5475 0.2 6.0 0.0 4.6 22.0 3.8 0.1 63.2 500 0.0 5.8 0.0 4.2 22.7 3.9 0.063.4 525 0.4 6.1 0.0 4.5 22.4 3.9 0.1 62.7 550 0.0 5.9 0.0 4.3 23.3 4.00.3 62.3 575 0.4 5.5 0.2 4.3 22.8 3.8 0.0 63.0 600 0.2 5.8 0.3 4.1 22.53.8 0.0 63.4 625 0.0 6.1 0.0 4.3 23.9 3.8 0.0 62.0 650 0.0 6.0 0.0 4.323.7 3.8 0.0 62.3 675 0.9 5.8 0.0 4.1 23.3 3.5 0.0 62.5 700 0.0 5.7 0.04.3 23.2 3.6 0.0 63.3 725 0.2 5.5 0.2 3.9 24.7 3.3 0.1 62.2 750 0.2 5.00.3 3.9 25.3 3.3 0.0 61.9 775 0.1 4.8 0.3 3.6 24.9 3.0 0.0 63.4 800 0.34.5 0.5 2.4 29.6 2.9 1.3 58.7 825 0.4 2.7 0.3 1.2 44.6 2.1 7.7 41.0 8500.2 1.6 0.2 0.6 57.0 1.2 19.4 19.9 875 0.1 0.8 0.2 0.3 63.0 0.6 25.6 9.5900 0.0 0.3 0.4 0.1 65.8 0.4 28.8 4.3 925 0.1 0.3 0.1 0.1 66.5 0.2 30.81.8 950 0.0 0.0 0.1 0.0 67.4 0.1 31.5 1.0 975 0.1 0.0 0.1 0.0 67.5 0.031.9 0.4 1000 0.5 0.0 0.3 0.0 67.1 0.1 31.7 0.4 1025 0.2 0.1 0.3 0.067.2 0.0 31.9 0.4 1050 0.0 0.0 0.2 0.1 67.3 0.0 32.0 0.3 1075 0.0 0.00.3 0.0 67.2 0.0 32.3 0.2 1100 0.0 0.1 0.3 0.1 67.0 0.0 32.3 0.3 11250.1 0.0 0.2 0.1 67.3 0.0 32.1 0.2 1150 0.3 0.0 0.2 0.1 66.7 0.0 32.5 0.21175 0.6 0.0 0.2 0.0 67.0 0.1 31.9 0.2 1200 0.2 0.0 0.3 0.0 67.3 0.031.9 0.3 1225 0.0 0.0 0.2 0.0 67.2 0.0 32.4 0.2 1250 0.3 0.0 0.3 0.167.0 0.0 32.3 0.1 1275 0.0 0.1 0.2 0.0 67.3 0.0 32.3 0.2 1300 0.0 0.00.2 0.0 67.3 0.0 32.2 0.2 1325 0.0 0.0 0.1 0.0 67.5 0.0 32.0 0.4 13500.2 0.0 0.1 0.0 67.4 0.0 32.2 0.2 1375 0.0 0.0 0.1 0.0 67.3 0.0 32.3 0.21400 0.4 0.0 0.1 0.0 67.1 0.0 32.1 0.2 1425 0.0 0.0 0.1 0.0 67.6 0.132.1 0.1 1450 0.0 0.0 0.2 0.0 66.9 0.0 32.6 0.3 1475 0.0 0.0 0.3 0.167.0 0.0 32.4 0.3 1500 0.0 0.0 0.1 0.0 67.1 0.0 32.6 0.2 1525 0.0 0.10.2 0.1 67.5 0.0 31.8 0.3 1550 0.2 0.1 0.2 0.0 67.2 0.0 32.0 0.3 15750.4 0.1 0.2 0.0 66.8 0.0 32.3 0.2 1600 0.0 0.0 0.2 0.0 67.3 0.1 31.9 0.51625 0.2 0.1 0.3 0.1 67.2 0.0 32.1 0.0 1650 0.1 0.0 0.1 0.0 67.3 0.132.2 0.2 1675 0.0 0.0 0.1 0.0 67.6 0.0 32.0 0.3 1700 0.0 0.0 0.1 0.067.1 0.0 32.4 0.3 1725 0.0 0.0 0.2 0.1 67.6 0.0 32.1 0.1 1750 0.0 0.00.3 0.0 67.1 0.1 32.3 0.2 1775 0.0 0.0 0.1 0.0 67.5 0.0 32.2 0.3 18000.0 0.1 0.1 0.0 67.2 0.0 32.5 0.2 1825 0.0 0.0 0.2 0.0 67.6 0.0 32.0 0.21850 0.0 0.0 0.3 0.1 67.4 0.0 32.0 0.2 1875 0.2 0.0 0.2 0.0 67.1 0.032.1 0.3

Similar to the non-annealed film, Tables XI, XII, and XIII show anatural passivation layer to be formed to a depth of about 25 Angstromson top of the ternary compound layer. The ternary compound layer has athickness of about 825 Angstroms to about 850 Angstroms and also has azinc concentration of about 62 atomic percent to about 68 atomicpercent, an oxygen concentration of about 18 atomic percent to about 25atomic percent, a nitride concentration of about 5.0 atomic percent toabout 6.3 atomic percent, and a nitrite concentration of about 3.0atomic percent to about 4.9 atomic percent for two weeks.

Increasing the flow ratio of nitrogen to oxygen may increase the amountof nitride formed in the ternary compound. Tables XIV, XV, and XVI showthe composition of the ternary compound as deposited and after one weekrespectively for an oxygen to argon to nitrogen flow ratio of 1:12:50 ata temperature of 50 degrees Celsius.

TABLE XIV Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 19.14.2 2.1 0.1 39.9 0.4 0.0 34.3 25 0.0 6.4 0.0 3.8 18.4 1.3 0.0 70.1 500.0 6.4 0.0 4.5 17.0 2.3 0.0 69.8 75 0.0 6.4 0.0 5.0 18.1 2.9 0.0 67.7100 0.2 5.8 0.0 4.5 18.6 3.4 0.0 67.5 125 0.0 6.1 0.0 4.7 18.4 3.4 0.067.5 150 0.0 6.1 0.0 4.7 18.3 3.2 0.0 67.6 175 0.2 5.9 0.0 4.8 19.0 3.30.0 66.9 200 0.6 6.3 0.0 5.1 18.5 3.8 0.8 65.0 225 0.0 6.1 0.0 4.8 17.84.0 0.0 67.2 250 0.2 6.1 0.0 4.7 17.5 3.7 0.4 67.5 275 1.1 5.8 0.0 4.918.9 3.8 0.0 65.5 300 0.0 5.8 0.0 4.7 18.5 3.6 0.0 67.4 325 0.0 5.8 0.04.7 18.1 3.7 0.6 67.2 350 0.0 5.9 0.0 5.0 19.3 3.7 0.0 66.0 375 0.0 6.30.0 4.9 19.3 3.7 0.0 65.8 400 0.6 6.2 0.0 5.1 17.2 3.8 0.0 67.1 425 0.05.9 0.0 4.9 18.9 3.5 0.0 66.9 450 0.0 6.1 0.0 4.6 19.6 3.7 0.3 65.7 4750.0 6.0 0.0 4.9 18.1 3.6 0.5 67.0 500 0.0 6.1 0.0 4.8 19.5 3.9 0.3 65.4525 0.7 6.1 0.0 4.9 18.6 3.7 0.4 65.6 550 0.0 6.2 0.0 4.8 19.3 3.6 0.865.3 575 0.7 5.8 0.0 5.0 19.8 3.9 0.3 64.7 600 0.1 6.3 0.0 4.7 18.2 3.70.0 67.0 625 0.0 5.8 0.0 4.7 20.0 3.9 0.0 65.6 650 0.5 6.1 0.0 4.7 18.83.5 0.6 65.8 675 1.4 4.5 1.2 2.6 29.8 3.2 3.2 54.2 700 0.8 1.5 1.5 0.852.4 1.9 17.2 24.0 725 0.4 0.3 1.1 0.3 63.2 1.1 25.1 8.6 750 0.6 0.1 0.50.1 66.6 0.4 28.8 3.0 775 0.0 0.0 0.2 0.0 68.2 0.2 30.4 0.9 800 0.5 0.10.1 0.0 67.8 0.2 31.0 0.4 825 0.2 0.1 0.1 0.0 68.0 0.1 31.5 0.2 850 0.00.0 0.1 0.0 68.3 0.0 31.4 0.2 875 0.0 0.1 0.0 0.0 68.3 0.0 31.3 0.2 9000.0 0.0 0.2 0.1 67.7 0.1 31.7 0.3 925 0.3 0.0 0.1 0.0 67.5 0.0 31.9 0.1950 0.4 0.0 0.0 0.0 67.7 0.0 31.7 0.2 975 0.1 0.0 0.0 0.0 67.9 0.0 31.90.1 1000 0.5 0.0 0.0 0.0 67.7 0.0 31.6 0.1 1025 0.5 0.0 0.1 0.0 67.8 0.031.6 0.1 1050 0.2 0.0 0.1 0.0 67.8 0.0 31.7 0.2 1075 0.0 0.0 0.1 0.068.3 0.0 31.4 0.2 1100 0.0 0.0 0.1 0.0 68.0 0.1 31.5 0.2 1125 0.0 0.00.0 0.0 68.2 0.0 31.7 0.1 1150 0.0 0.0 0.0 0.0 68.0 0.1 31.8 0.2 11750.0 0.0 0.1 0.0 68.0 0.0 31.8 0.1 1200 0.2 0.0 0.1 0.0 67.8 0.0 31.8 0.21225 0.3 0.1 0.1 0.0 67.8 0.0 31.6 0.2 1250 0.2 0.0 0.0 0.0 68.0 0.031.6 0.2

TABLE XV Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 22.70.4 1.6 0.0 43.3 0.2 0.0 31.8 25 0.6 2.7 0.6 0.9 34.4 0.6 0.0 60.2 500.0 4.8 0.0 2.4 25.1 0.7 0.1 66.8 75 0.7 5.4 0.0 3.4 19.1 1.4 0.1 69.9100 0.1 6.0 0.0 4.3 17.8 2.4 0.1 69.4 125 0.5 6.3 0.0 4.6 17.9 2.9 0.867.1 150 0.0 6.2 0.0 4.9 17.4 3.3 0.1 68.1 175 0.2 6.1 0.0 4.9 17.2 3.40.0 68.2 200 0.1 6.3 0.0 4.9 18.0 3.7 0.3 66.7 225 0.0 6.3 0.0 4.8 17.83.6 0.3 67.2 250 1.1 5.8 0.0 4.8 17.0 3.8 0.0 67.6 275 0.3 6.5 0.0 4.916.9 3.6 0.0 67.9 300 0.3 6.2 0.0 5.1 17.1 3.3 0.4 67.5 325 0.0 6.2 0.04.9 18.1 3.5 0.4 66.9 350 0.3 6.1 0.0 4.6 17.3 3.3 0.0 68.4 375 0.0 6.70.0 4.8 17.2 3.6 0.0 67.8 400 0.4 6.1 0.0 4.8 17.4 3.7 0.0 67.7 425 1.15.9 0.0 4.9 18.5 3.7 0.0 66.1 450 0.0 6.0 0.0 4.9 18.4 3.5 0.1 67.1 4750.4 6.1 0.0 4.8 17.6 3.5 0.7 66.9 500 0.6 6.2 0.0 4.5 18.8 3.4 0.2 66.4525 0.0 5.7 0.0 4.8 17.7 3.5 0.0 68.3 550 0.2 6.0 0.0 5.0 18.7 3.6 0.266.4 575 0.2 6.4 0.0 4.9 18.5 3.4 0.0 66.6 600 0.5 6.2 0.0 4.9 18.1 3.50.0 66.8 625 0.2 5.9 0.0 5.0 18.3 3.5 0.3 66.8 650 0.1 6.7 0.0 5.0 17.73.4 0.4 66.9 675 0.0 6.0 0.0 4.9 19.5 3.5 0.0 66.2 700 1.2 5.8 0.0 3.921.5 3.5 1.5 62.7 725 0.7 3.3 1.1 1.8 38.8 2.9 9.9 41.7 750 0.1 1.4 1.10.7 54.6 1.6 21.1 19.4 775 0.0 0.6 0.7 0.3 62.7 1.0 26.6 8.2 800 0.2 0.10.4 0.1 65.4 0.5 30.0 3.3 825 0.2 0.1 0.3 0.1 66.8 0.2 31.2 1.2 850 0.30.1 0.1 0.0 67.1 0.1 31.9 0.5 875 0.0 0.0 0.0 0.0 67.8 0.0 31.9 0.3 9000.1 0.1 0.1 0.0 66.9 0.0 32.6 0.2 925 0.2 0.0 0.1 0.0 67.1 0.0 32.4 0.2950 0.0 0.0 0.1 0.1 66.9 0.1 32.5 0.4 975 0.2 0.0 0.0 0.0 67.0 0.0 32.50.2 1000 0.4 0.2 0.1 0.0 66.9 0.1 32.2 0.1 1025 0.0 0.0 0.1 0.0 67.3 0.032.4 0.2 1050 0.1 0.1 0.1 0.0 66.9 0.1 32.6 0.1 1075 0.1 0.0 0.0 0.067.0 0.0 32.6 0.3 1100 0.1 0.0 0.0 0.0 67.2 0.0 32.5 0.1 1125 0.2 0.00.0 0.0 67.0 0.1 32.4 0.2 1150 0.3 0.0 0.0 0.0 66.9 0.0 32.5 0.3 11750.0 0.0 0.1 0.0 67.1 0.0 32.6 0.2 1200 0.2 0.0 0.1 0.0 67.1 0.0 32.5 0.11225 0.0 0.0 0.0 0.0 67.5 0.0 32.2 0.3 1250 0.1 0.0 0.1 0.0 67.0 0.032.7 0.1 1275 0.0 0.0 0.1 0.1 66.9 0.0 32.8 0.1 1300 0.4 0.1 0.1 0.066.8 0.0 32.5 0.2 1325 0.0 0.0 0.0 0.0 67.4 0.1 32.3 0.2 1350 0.3 0.00.0 0.0 66.8 0.0 32.6 0.3 1375 0.0 0.1 0.1 0.0 67.2 0.1 32.5 0.1 14000.3 0.1 0.1 0.0 67.3 0.0 32.2 0.1 1425 0.0 0.0 0.0 0.0 67.1 0.1 32.5 0.21450 0.1 0.0 0.0 0.0 67.2 0.0 32.6 0.2 1475 0.0 0.0 0.0 0.0 67.3 0.032.5 0.1 1500 0.2 0.0 0.1 0.0 67.3 0.1 32.2 0.1

TABLE XVI Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 21.30.0 0.6 0.0 44.7 0.3 0.4 32.7 25 1.4 0.0 0.2 0.0 42.4 0.6 0.0 55.4 500.7 0.0 0.2 0.0 41.6 0.4 0.0 57.0 75 1.2 0.0 0.2 0.0 40.8 0.6 0.2 57.1100 0.6 0.1 0.2 0.0 41.5 0.6 0.0 57.0 125 0.6 0.1 0.1 0.0 42.2 0.6 0.056.4 150 0.1 0.1 0.1 0.0 41.2 0.7 0.0 57.8 175 0.3 0.0 0.2 0.0 41.1 0.50.1 57.8 200 0.2 0.1 0.2 0.0 41.7 0.5 0.0 57.4 225 0.0 0.1 0.2 0.0 41.20.7 0.2 57.6 250 0.4 0.2 0.2 0.0 40.8 0.7 0.0 57.8 275 1.3 0.0 0.2 0.040.4 0.7 0.0 57.4 300 0.3 0.0 0.1 0.0 41.0 0.7 0.0 57.9 325 0.3 0.1 0.30.1 41.5 0.6 0.0 57.2 350 0.3 0.4 0.3 0.1 40.0 0.7 0.3 58.0 375 0.0 0.60.2 0.2 39.0 0.8 0.0 59.2 400 0.9 1.3 0.3 0.4 37.1 0.8 0.4 58.8 425 0.61.3 0.3 0.6 36.0 1.0 0.1 60.3 450 0.6 2.0 0.2 1.0 34.1 1.2 0.2 60.9 4751.3 2.5 0.3 1.4 30.7 1.1 0.1 62.8 500 0.4 3.4 0.0 1.8 28.0 1.7 0.7 64.0525 0.1 4.1 0.0 2.3 26.0 1.8 1.0 64.7 550 0.5 4.3 0.0 2.7 24.4 2.1 0.665.4 575 0.3 5.2 0.0 3.4 21.6 2.6 0.8 66.2 600 0.9 5.7 0.0 3.5 20.5 2.90.2 66.3 625 0.4 5.7 0.0 4.0 20.0 3.1 0.5 66.3 650 0.1 6.0 0.0 4.2 18.83.2 0.6 67.0 675 0.0 6.1 0.0 4.3 18.2 3.6 0.8 67.1 700 0.1 6.3 0.0 4.418.7 3.6 0.4 66.5 725 0.1 6.2 0.0 4.4 17.4 3.7 0.2 68.0 750 0.0 6.3 0.04.5 17.7 3.6 1.1 66.7 775 0.0 6.3 0.0 4.5 19.3 3.4 0.7 65.8 800 0.6 6.20.0 4.1 19.0 3.7 0.8 65.6 825 0.4 6.3 0.0 4.3 17.9 3.4 0.8 66.8 850 0.06.3 0.0 4.2 19.2 3.5 1.0 65.8 875 0.0 6.1 0.0 4.2 19.5 3.5 1.0 65.7 9000.0 6.4 0.0 4.4 18.2 3.9 1.1 66.0 925 0.0 6.3 0.0 4.6 19.2 3.8 0.9 65.2950 0.2 6.5 0.0 4.1 20.0 3.8 1.3 64.1 975 0.5 6.3 0.0 3.8 21.6 3.6 2.062.2 1000 0.0 5.9 0.0 3.7 25.7 3.2 4.3 57.2 1025 0.3 5.0 0.0 2.9 32.03.0 7.6 49.3 1050 0.3 4.1 0.0 2.1 38.9 2.4 12.4 39.9 1075 0.8 3.3 0.01.5 46.1 1.9 17.2 29.3 1100 0.6 1.9 0.3 0.9 53.3 1.4 21.2 20.5 1125 0.41.5 0.3 0.6 58.3 1.0 24.8 13.2 1150 0.2 0.9 0.4 0.4 61.6 0.7 27.7 8.11175 0.7 0.3 0.5 0.2 64.3 0.3 29.0 4.8 1200 0.1 0.4 0.2 0.1 65.9 0.230.5 2.7 1225 0.0 0.2 0.3 0.1 66.6 0.1 31.1 1.5 1250 0.0 0.1 0.3 0.067.1 0.1 31.7 0.9 1275 0.5 0.0 0.2 0.0 67.2 0.0 31.8 0.3 1300 0.5 0.10.2 0.0 67.2 0.1 31.8 0.2 1325 0.1 0.0 0.1 0.0 67.6 0.0 31.9 0.2 13500.1 0.0 0.2 0.0 67.3 0.0 32.2 0.1 1375 0.3 0.0 0.3 0.0 67.5 0.0 32.0 0.01400 0.0 0.0 0.2 0.0 67.8 0.0 31.9 0.0 1425 0.2 0.0 0.2 0.0 67.6 0.131.9 0.1 1450 0.1 0.0 0.2 0.0 67.7 0.0 31.9 0.0 1475 0.1 0.0 0.1 0.067.7 0.0 32.0 0.1 1500 0.0 0.0 0.1 0.0 67.9 0.0 31.9 0.0 1525 0.0 0.00.1 0.0 67.6 0.1 32.0 0.2 1550 0.4 0.0 0.2 0.0 67.6 0.0 31.8 0.0 15750.0 0.0 0.2 0.1 67.7 0.0 31.9 0.1 1600 0.1 0.0 0.1 0.0 67.7 0.0 31.9 0.11625 0.0 0.0 0.1 0.0 67.9 0.0 32.0 0.1 1650 0.1 0.1 0.3 0.1 67.7 0.031.9 0.0 1675 0.0 0.0 0.2 0.0 67.5 0.0 32.3 0.0 1700 0.0 0.0 0.2 0.067.4 0.1 32.3 0.1 1725 0.1 0.0 0.2 0.0 67.8 0.0 31.9 0.0 1750 0.3 0.00.1 0.0 67.4 0.0 32.1 0.1 1775 0.2 0.1 0.3 0.0 67.6 0.0 31.6 0.2 18000.0 0.0 0.2 0.0 67.9 0.0 31.8 0.1 1825 0.2 0.0 0.2 0.0 67.5 0.0 32.0 0.01850 0.4 0.1 0.3 0.1 67.3 0.0 31.8 0.1 1875 0.0 0.0 0.2 0.1 67.7 0.032.1 0.0

As may be seen from Tables XIV, XV, and XVI, a natural passivation layerforms to a depth of about 25 Angstroms on top of the ternary compoundlayer. The ternary compound layer has a thickness of about 700 Angstromsto about 750 Angstroms and also has a zinc concentration of about 65atomic percent to about 70 atomic percent, an oxygen concentration ofabout 17 atomic percent to about 20 atomic percent, a nitrideconcentration of about 5.7 atomic percent to about 6.4 atomic percent,and a nitrite concentration of about 3.4 atomic percent to about 5.1atomic percent after one week. After two weeks, the zinc concentrationchanges to about 55 atomic percent to about 68 atomic percent, theoxygen concentration changes to about 17 atomic percent to about 42atomic percent, the nitride concentration changes to about 0.4 atomicpercent to about 6.4 atomic percent, and the nitrite concentrationchanges to about 0.2 atomic percent to about 4.5 atomic percent.

When the film is annealed, the composition of the film remainssubstantially the same as the non-annealed film. Tables XVII, XVIII, andXIX show the composition of the annealed ternary compound of Tables XIV,XV, and XVI respectively.

TABLE XVII Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 018.5 8.8 0.6 0.3 31.8 0.8 0.0 39.1 25 0.0 6.0 0.2 4.0 15.7 1.8 0.0 72.350 0.2 6.2 0.0 4.5 16.3 2.8 0.0 70.1 75 0.0 6.1 0.1 4.8 16.9 2.9 0.668.6 100 0.3 5.9 0.2 4.7 17.4 3.3 0.4 67.9 125 0.0 6.0 0.2 4.9 16.5 3.40.0 69.1 150 0.0 6.3 0.0 5.1 16.3 3.3 0.0 69.1 175 0.0 6.2 0.0 5.0 18.33.2 0.0 67.3 200 0.0 6.3 0.0 5.1 16.8 3.5 0.0 68.3 225 0.0 6.0 0.0 5.217.3 3.6 0.0 67.9 250 0.2 6.0 0.0 5.1 18.2 3.8 0.1 66.7 275 0.0 6.0 0.05.1 18.1 3.8 0.4 66.7 300 0.0 5.9 0.1 5.6 18.2 3.5 0.0 66.8 325 0.8 6.10.0 5.4 17.6 3.6 0.0 66.7 350 0.0 6.1 0.0 5.3 18.8 3.6 0.2 66.0 375 0.46.3 0.0 5.3 17.7 3.7 0.0 66.6 400 0.0 6.2 0.0 5.4 17.6 3.6 0.3 67.0 4250.5 6.0 0.0 5.2 18.6 3.4 0.8 65.5 450 0.0 6.2 0.2 5.5 17.8 3.5 0.0 66.9475 1.1 6.0 0.1 5.3 18.5 3.6 0.0 65.4 500 1.0 6.1 0.1 5.3 18.2 3.6 0.065.7 525 0.0 6.1 0.1 5.4 17.9 4.1 0.0 66.3 550 0.0 5.9 0.0 5.2 18.5 3.70.3 66.5 575 0.4 5.9 0.5 5.6 18.6 3.5 0.0 65.6 600 0.0 5.9 0.2 5.5 19.23.5 0.5 65.2 625 0.0 5.8 0.2 5.0 19.3 3.7 0.3 65.8 650 0.1 5.6 0.3 5.219.9 3.6 0.2 65.0 675 1.3 4.2 1.4 3.2 27.8 3.3 2.2 56.7 700 0.4 1.6 1.21.0 50.4 2.0 15.6 27.9 725 0.0 0.6 0.8 0.5 61.1 1.0 25.6 10.4 750 0.00.3 0.4 0.2 66.0 0.4 29.0 3.7 775 0.0 0.1 0.3 0.1 67.4 0.2 30.7 1.3 8000.0 0.0 0.2 0.0 67.6 0.1 31.6 0.5 825 0.4 0.0 0.1 0.0 67.3 0.1 32.0 0.1850 0.0 0.0 0.1 0.0 67.5 0.1 32.2 0.1 875 0.4 0.1 0.1 0.0 67.2 0.1 32.00.0

TABLE XVIII Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 024.7 6.8 1.6 0.3 32.9 0.4 0.0 33.4 25 0.0 6.3 0.0 3.8 16.2 1.5 0.8 71.450 0.0 6.6 0.0 4.3 18.0 2.7 0.3 68.2 75 0.0 6.2 0.0 4.7 16.6 3.0 0.469.0 100 0.1 6.3 0.0 4.6 17.8 3.3 0.3 67.6 125 0.1 6.2 0.0 4.6 18.0 3.20.7 67.2 150 0.2 6.1 0.0 5.1 17.1 3.4 0.6 67.7 175 0.0 6.2 0.0 4.7 17.73.4 0.8 67.2 200 0.0 6.0 0.1 4.9 17.4 3.5 0.0 68.2 225 0.7 6.1 0.0 4.618.0 3.9 0.9 65.8 250 0.5 6.1 0.0 4.6 18.3 3.5 0.0 67.0 275 0.0 5.9 0.04.9 18.3 3.8 0.4 66.7 300 0.2 6.2 0.0 5.0 18.7 3.8 0.0 66.1 325 0.0 5.90.0 4.8 18.6 3.5 0.0 67.2 350 0.3 5.9 0.0 4.9 18.3 3.8 0.1 66.7 375 0.25.7 0.0 4.6 19.0 3.6 0.4 66.5 400 0.1 6.0 0.0 4.8 18.3 4.0 0.5 66.4 4250.0 6.2 0.0 4.9 18.7 3.8 0.4 65.9 450 0.0 5.9 0.0 4.7 18.7 3.9 0.3 66.4475 0.1 6.2 0.0 4.8 18.2 3.9 0.4 66.5 500 0.3 6.4 0.0 4.6 18.2 3.5 0.466.7 525 0.0 6.1 0.0 4.6 19.3 3.9 0.0 66.1 550 0.3 6.1 0.0 4.7 19.6 3.80.0 65.4 575 0.0 6.1 0.0 4.5 19.1 3.8 0.5 66.1 600 0.0 6.2 0.0 4.6 18.54.1 0.0 66.7 625 0.7 6.3 0.0 4.8 18.3 3.6 0.0 66.3 650 0.2 5.8 0.2 4.719.4 3.7 0.9 65.1 675 0.0 6.2 0.0 4.5 20.4 3.5 0.7 64.7 700 0.6 4.4 0.92.5 31.0 3.1 3.9 53.7 725 0.5 2.1 0.6 0.9 52.0 1.9 17.1 25.0 750 0.2 0.41.1 0.4 61.8 0.9 25.4 9.8 775 0.6 0.4 0.4 0.1 65.1 0.5 29.0 3.8 800 0.00.1 0.3 0.0 67.5 0.3 30.5 1.2 825 0.0 0.1 0.1 0.0 67.7 0.2 31.5 0.4 8500.2 0.0 0.2 0.0 67.9 0.1 31.4 0.1 875 0.0 0.0 0.1 0.1 67.7 0.1 32.1 0.0900 0.0 0.0 0.0 0.0 68.0 0.1 31.9 0.1 925 0.1 0.0 0.1 0.1 67.4 0.1 32.20.0 950 0.0 0.1 0.1 0.0 68.2 0.0 31.6 0.0 975 0.0 0.1 0.1 0.0 67.7 0.032.2 0.0 1000 0.3 0.0 0.0 0.0 67.7 0.0 32.0 0.0 1025 0.0 0.0 0.1 0.167.8 0.0 32.1 0.0 1050 0.0 0.0 0.1 0.0 67.8 0.0 32.2 0.0 1075 0.0 0.00.1 0.0 67.9 0.1 32.0 0.0 1100 0.0 0.0 0.1 0.0 67.8 0.0 32.1 0.0 11250.1 0.0 0.1 0.0 68.0 0.1 31.8 0.0 1150 0.0 0.0 0.1 0.0 67.6 0.0 32.3 0.01175 0.2 0.0 0.1 0.0 67.5 0.1 32.1 0.0 1200 0.2 0.1 0.1 0.0 67.9 0.031.8 0.0 1225 0.0 0.0 0.1 0.1 67.5 0.0 32.3 0.0 1250 0.3 0.0 0.1 0.067.9 0.0 31.8 0.0 1275 0.0 0.1 0.1 0.0 67.9 0.0 32.0 0.0 1300 0.0 0.00.1 0.0 67.9 0.0 31.9 0.0 1325 0.0 0.0 0.1 0.0 67.7 0.0 32.2 0.0 13500.0 0.0 0.1 0.0 67.7 0.0 32.2 0.0 1375 0.1 0.0 0.1 0.0 67.6 0.1 32.1 0.01400 0.0 0.0 0.1 0.0 67.5 0.0 32.3 0.1 1425 0.0 0.0 0.1 0.0 68.1 0.031.8 0.0 1450 0.0 0.0 0.1 0.0 68.1 0.0 31.9 0.0 1475 0.3 0.0 0.1 0.067.5 0.0 32.0 0.2 1500 0.1 0.0 0.1 0.0 68.0 0.0 31.8 0.0

TABLE XIX Sputter Depth (Å) C Nitrides Organic N NO₂ O Al SiO₂ Zn 0 22.36.8 1.1 0.0 33.0 0.5 0.0 36.3 25 0.0 6.2 0.0 3.8 17.2 1.1 0.4 71.4 500.0 6.1 0.0 4.3 16.0 2.3 0.3 71.0 75 0.0 6.1 0.0 4.7 16.4 2.7 0.2 69.9100 0.1 6.1 0.0 4.7 16.5 3.2 0.2 69.3 125 1.1 6.0 0.0 4.7 15.6 3.1 0.069.7 150 0.0 6.1 0.0 5.0 16.3 3.4 0.1 69.1 175 0.1 5.9 0.0 5.0 17.8 3.40.3 67.5 200 0.0 6.2 0.2 5.3 16.6 3.3 0.0 68.4 225 0.0 5.9 0.0 4.5 17.43.6 0.2 68.4 250 0.0 6.1 0.2 4.8 17.6 3.6 0.6 67.2 275 0.0 5.8 0.0 5.118.8 3.4 0.1 66.8 300 0.1 5.7 0.0 5.1 17.8 3.5 0.3 67.6 325 0.2 5.9 0.05.1 18.1 3.6 0.0 67.1 350 0.0 6.0 0.0 4.6 18.2 3.6 0.0 67.7 375 0.0 6.10.0 5.2 17.2 3.8 0.0 67.8 400 0.2 6.1 0.0 5.0 17.3 3.2 0.1 68.0 425 0.46.0 0.0 5.1 17.5 3.5 0.5 66.9 450 0.4 5.9 0.0 4.7 18.7 3.3 0.3 66.8 4750.0 5.9 0.0 4.8 18.2 3.7 0.4 67.0 500 0.0 6.3 0.0 4.9 17.6 3.7 0.4 67.2525 0.0 6.0 0.0 4.9 18.4 3.5 0.3 66.9 550 0.7 6.0 0.0 4.9 18.6 3.5 0.465.9 575 0.1 6.0 0.0 4.7 19.1 3.7 0.0 66.5 600 0.0 5.9 0.1 5.0 18.7 3.50.2 66.7 625 0.0 6.2 0.0 4.7 18.0 3.5 0.4 67.2 650 0.0 6.0 0.0 4.7 19.83.6 0.2 65.7 675 0.6 5.9 0.0 4.2 19.7 3.3 0.8 65.5 700 1.1 4.3 0.0 1.636.3 2.6 6.6 47.5 725 0.3 2.5 0.0 0.5 55.6 1.6 20.0 19.5 750 0.3 1.1 0.00.1 63.7 0.9 26.9 7.0 775 0.0 0.7 0.2 0.0 66.1 0.5 30.1 2.5 800 0.0 0.40.1 0.0 67.2 0.2 31.3 0.7 825 0.2 0.1 0.3 0.1 67.1 0.1 31.9 0.4 850 0.00.0 0.2 0.1 67.5 0.1 31.8 0.3 875 0.2 0.0 0.2 0.0 66.9 0.1 32.3 0.4 9000.0 0.0 0.2 0.0 67.2 0.1 32.2 0.3 925 0.0 0.1 0.2 0.0 67.4 0.0 32.2 0.1950 0.3 0.1 0.3 0.1 67.0 0.0 32.0 0.2 975 0.0 0.0 0.1 0.0 67.4 0.1 32.30.2 1000 0.1 0.0 0.2 0.0 67.5 0.1 32.1 0.1 1025 0.3 0.0 0.1 0.0 67.5 0.031.8 0.2 1050 0.0 0.0 0.2 0.0 67.5 0.0 32.2 0.1 1075 0.7 0.0 0.0 0.067.0 0.0 32.1 0.2 1100 0.1 0.1 0.1 0.0 67.0 0.0 32.4 0.2 1125 0.0 0.00.1 0.0 67.4 0.0 32.3 0.1

As may be seen from Tables XVII, XVIII, and XIX, a natural passivationlayer forms to a depth of about 25 Angstroms to about 50 Angstroms ontop of the ternary compound layer. The ternary compound layer has athickness of about 700 Angstroms to about 725 Angstroms and also has azinc concentration of about 65 atomic percent to about 72 atomicpercent, an oxygen concentration of about 16 atomic percent to about 20atomic percent, a nitride concentration of about 5.6 atomic percent toabout 6.6 atomic percent, and a nitrite concentration of about 3.8atomic percent to about 5.6 atomic percent after two weeks.

Normally, the ternary compound layer will not be the topmost layer in astructure. Rather, the ternary compound layer may be passivated by someother layer such as silicon nitride, silicon oxide, silicon carbide, orsome other organic passivation layer. The above tables show that aternary compound layer produced with a high nitrogen gas flow rate maygo at least as long as 2 weeks before a passivation layer is depositedthereon. In one embodiment, the ternary compound layer produced with ahigh nitrogen gas flow rate and without annealing may go as long as 3weeks before a passivation layer is deposited thereon. In anotherembodiment, the ternary compound layer produced with a high nitrogen gasflow rate annealed at 400 degrees Celsius may go as long as 4 weeksbefore a passivation layer is deposited thereon.

Because both nitrite and nitride components are present in the ternarycompound, a peak for both the nitride and the nitrite may be seen inX-ray Photoelectron Spectroscopy (XPS) measurements. The nitrite peakmay be present between about 399 and 404 eV binding energy with anintensity of between about 5,500 to about 12,000 while the nitride maybe present between about 393 to about 396 eV with an intensity of about5,500 to about 12,000. The ratio of the nitride peak to the nitrite peakas measured by XPS may fall within the range of about 3:5 to about 5:3.The nitride (N₂O) peak may be an artifact due to sputtering the samplewhich made the oxygen and nitrogen from the film to form a chemicalstate that is different from the one in the film.

The ternary compound may have a band gap between about 3.1 eV to about1.2 eV, which equates to about 400 nm to about 1,000 nm. Thus, theternary compound has a band gap sufficiently low to cover the visiblerange of light and thus may be useful in solar applications. The bandgap energy may be tuned according to the amount of oxygen provided. Byproviding a higher amount of oxygen, the band gap may be increased. Thedependent of band gap to oxygen flow rate is almost independent ofnitrogen flow rate in a large flow rate regime. During deposition, theband gap energy for the ternary film may be graded to fine tune the banggap throughout the film. For example, it may be desirable to have ahigher band gap energy near the surface of the ternary compound layerand then adjust the band gap energy throughout the thickness of theternary compound layer. By controlling the proportionate amount ofoxygen provided relative to the amount of argon and nitrogen provided,the band gap energy distribution for the ternary compound may becontrolled during deposition.

By reactive sputtering a zinc target in an atmosphere of nitrogen andoxygen where the flow rate of nitrogen is significantly greater than theflow rate of oxygen, a stable semiconductor film may be formed that hasa mobility greater than amorphous silicon. It is to be understood thatthe semiconductor film discussed herein may be produced by other methodsbesides reactive sputtering.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A deposition method comprising: positioning a substrate in asputtering chamber, the sputtering chamber comprising a zinc-containingtarget; delivering a sputtering gas to the sputtering chamber;activating the sputtering gas; and depositing a semiconductor layer on asubstrate, the semiconductor layer comprising a ternary compound ofzinc, oxygen and nitrogen, wherein the semiconductor layer has atransmittance of less than 80 percent.
 2. The deposition method of claim1, further comprising annealing the semiconductor layer.
 3. Thedeposition method of claim 1, wherein the semiconductor layer isannealed at a temperature of about 400 degrees C.
 4. The depositionmethod of claim 1, wherein the sputtering gas comprises anoxygen-containing gas and a nitrogen-containing gas.
 5. The depositionmethod of claim 4, wherein the oxygen-containing gas and anitrogen-containing gas are delivered at a flow ratio of 10:1 to 100:1.6. The deposition method of claim 1, wherein the ternary compoundcomprises ZnN_(x)O_(y).
 7. The deposition method of claim 1, wherein thesputtering gas further comprises B₂H₆, CO₂, CO, CH₄ or combinationsthereof.
 8. The deposition method of claim 1, wherein the ternarycompound comprises a dopant.
 9. The deposition method of claim 1,wherein the dopant is aluminum.
 10. A semiconductor film comprising aternary compound of zinc, oxygen and nitrogen, the semiconductor layerhaving a transmittance of less than 80 percent.
 11. The semiconductorfilm of claim 10, wherein the ternary compound comprises a first portionwith a first band gap energy and a second portion with a second band gapenergy, the second band gap energy being higher than the first band gapenergy.
 12. The semiconductor film of claim 10, wherein the ternarycompound has a gradient band gap energy.
 13. The semiconductor film ofclaim 10, wherein the ternary compound comprises a dopant.
 14. Thesemiconductor film of claim 13, wherein the dopant is aluminum.
 15. Thesemiconductor film of claim 10, wherein the semiconductor layer isamorphous.